The present invention relates generally to the field of electrical transformers such as those used to control the transfer electrical energy from one circuit to another as well as provide voltage isolation between the control and power circuits. More particularly, the present invention relates to transformers that may be made on or in control electrical circuit boards, and to methods for making such transformers.
High speed transformers are used in a wide range of applications. For example, in power converters capable of converting electrical energy for use with centrifuges, magnetic clutches, pumps and more generally, in electric motor drive controllers that transform and condition incoming AC power for supply to motor drive circuitry. In certain motor drive circuits, silicon controlled rectifiers (SCRs) or other solid state switches are utilized to redirect and rectify incoming AC power and to deliver variable voltage and frequency three-phase power to control the speed of an induction motor. Accordingly, pulse transformers may be employed to provide voltage isolation and drive, i.e., switch solid state switches, according to different phases of the incoming AC power. However, pulse transformers may not provide adequate voltage isolation.